A radiographic image represented by an X-ray image and captured by using radiation has found widespread application for the purpose of disease diagnosis and others. The radiographic image for medical treatment was captured using a screen film in the conventional method. However, the realized digitization of a radiographic image in recent years has allowed a CR (Computed Radiography) apparatus to come into widespread use, for example, wherein the radiation having passed through a subject is accumulated on a stimulable phosphor sheet in which a stimulable phosphor layer is formed. The stimulable phosphor sheet is then scanned by a beam of laser, so that the stimulable light emitted from the stimulable phosphor sheet is subjected to photoelectric conversion, whereby image data is obtained.
When a CR device is used for radiographic imaging, the cassette (e.g., Patent Literatures 1 through 3, hereinafter referred to as “CR cassette”) incorporating such a recording medium as a screen film or stimulable phosphor sheet is often kept loaded on the bucky device or the like. This CR cassette is often designed and manufactured according to the JIS-specified size for the conventional screen film cassette so that this CR cassette can be used after being mounted on the existing bucky device introduced for use with the conventional screen film cassette mounted thereon.
When the CR cassette is designed and manufactured in this manner, the size of the screen film cassette is made uniform with that of the CR cassette, and effective use of the existing facility for the screen film can be ensured with the interchangeability maintained between the two. This arrangement also allows the image data to be digitalized.
The radiographic image capturing devices for medical treatment developed in recent years include a FPD (Flat Panel Detector) which is a detector for acquiring digital image data by detecting the radiation having been applied, namely, a radiographic imaging device. This is further developed into a portable radiographic imaging device having sizes interchangeable with a CR cassette wherein the aforementioned FPD is incorporated in a housing (Patent Literature 4).
Since the FPD cassette having a size interchangeable with such a CR cassette is portable, one FPD cassette is assumed to be used commonly in various radiographing chambers. Thus, the systems disclosed so far includes a system in which, when used in combination with the X-ray tube and bucky device arranged in each of the radiographing chambers, the correction optimum to each combination is applied to the image data obtained from the FPD cassette, whereby uniform image data is provided in the final phase (Patent Literatures 5 and 6).
Patent Literature 7 discloses a specific method for combination detection in which an FPD cassette is equipped with a fixed detecting section and mark detecting section, and, when the FPD cassette is loaded on the cassette holder of the bucky device, and the fixed detecting section of the FPD cassette has come in contact with the fixed portion provided on the bucky device, the mark detecting section of the FPD cassette reads the mark of the cassette holder. Then the ID information of the bucky device recorded in the mark and the ID information of the FPD cassette are sent to an external device through a cable so as to select an image processing (correction) parameter best suited to the radiographing.